Print Email Facebook Twitter Increased sustainability of softening by producing pure calcite pellets for reuse Title Increased sustainability of softening by producing pure calcite pellets for reuse Author Hofs, B (KWR Water Research Institute) Baars, ET (Waternet) Palmen, LJ (KWR Water Research Institute) Elings, JA (Reststoffenunie Waterleidingbedrijven) Kors, L.J. (Waternet) Kramer, O.J.I. (TU Delft Sanitary Engineering; Waternet) Koppers, H (Reststoffenunie Waterleidingbedrijven) van der Hoek, J.P. (TU Delft Sanitary Engineering) Date 2015 Abstract About 50% of the drinking water in the Netherlands is centrally softened by the drinking water companies in a process known as pellet softening. In this process a base and seeding material are mixed in an upflow reactor, where subsequently CaCO3 precipitates on a seed core as pellets. The seeding material is usually sand, but recently CaCO3 was introduced as seeding material at several full scale plants. The pure calcite pellets that are produced as a by-product in these plants can be reused as seeding material, after grinding and sieving part of the produced pellets. The main advantages of this reuse are an expected significant decrease of the ecological footprint of both calcite as raw material and the drinking water treatment plants using pellet softening, and increased valorisation of the pellets. However, the handling and processing of the pellets and seeding material should be such, that microbiological and chemical contamination risks of the drinking water are negligible. This research shows that grinded and sieved CaCO3 outperforms commercial CaCO3 and that microbiological risks can be adequately controlled. Subject calcium carbonateprecipitationpellet softening To reference this document use: http://resolver.tudelft.nl/uuid:7fa65d83-6948-4467-943e-aff04c0deacf Source AIWW Conference: Integrated Solutions for a Circular Economy and Resilient Cities Event Amsterdam international water week 2015 conference, 2015-11-02 → 2015-11-06, Amsterdam, Netherlands Part of collection Institutional Repository Document type conference paper Rights © 2015 B Hofs, ET Baars, LJ Palmen, JA Elings, L.J. Kors, O.J.I. Kramer, H Koppers, J.P. van der Hoek Files PDF hofs_calcite_aiww2015.pdf 312.3 KB Close viewer /islandora/object/uuid:7fa65d83-6948-4467-943e-aff04c0deacf/datastream/OBJ/view